Unattended ground sensor assembly

ABSTRACT

There is provided a ground sensor assembly adapted for deployment from air to a selected ground location. The ground sensor assembly comprises an aerially deployable sensor housing which has upper and lower housing ends defining a longitudinally elongated aperture therebetween. A plurality of connected sensor modules are longitudinally inserted into the aperture between the upper and lower housing ends. Furthermore, an aerodynamic module is connected to the sensor modules and is disposed adjacent the upper housing end outside the aperture. This aerodynamic module has a plurality of stabilizers which radially extend outward therefrom and form a generally parallel relationship with the upper housing end. Such stabilizers provide aerodynamic stability during the deployment of the ground sensor assembly from the air to the selected ground location.

STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT

This invention was made with Government support under N66001-98-C-8518awarded by the Department of the Navy. The Government has certain rightsto this invention.

CROSS-REFERENCE TO RELATED APPLICATIONS

Not Applicable

BACKGROUND OF THE INVENTION

The present invention relates generally to ground sensors, and moreparticularly to an improved ground sensor assembly which is aeriallydeployable to a precise ground location through the use of its radiallyextending stabilizers to position a plurality of longitudinally stackedsensor modules thereat.

The use of ground sensors for conducting surveillance activities havebeen known for years. These sensors are typically designed to performspecific functions such as gathering intelligence data in regards tomagnetic field activities, seismic activities or acoustic activities ofa particular ground location. The ground sensors would relay thegathered data back to the field command unit for analysis and use invarious field operations.

In the past, the ground sensors generally required human presence at theground location to be surveyed for their operations. However, they haveevolved over the years to operate without the need for any humaninteraction at such ground location. Once positioned at the targetedground location, the ground sensors are automatically set up to monitortherearound and collect field data for relay of the same to the commandunit.

Although the ground sensors may be delivered to the targeted groundlocation through various means, they are typically deployed from the airfrom an aircraft, for example, to the ground location. Such means ofdelivery is not only efficient but especially useful when the groundlocation to be targeted and surveyed is situated within an enemy orunfriendly territory.

Pinpoint accuracy of their placement is a must given that the desiredperipheral surveillance of the ground location may be compromised if theground sensors become displaced to even the slightest degree. However,by the nature of their design, many ground sensors commonly becomealtered in direction during their aerial deployment toward the targetedground location. In this regard, optimal peripheral surveillance wereoftentimes not achieved which led to unsought compromises in the overallfield operation.

Furthermore, the aerially-deployable ground sensors are essentiallydesigned and built to conduct a specific mission of gathering eithermagnetic field, seismic or acoustic data. These ground sensors aregenerally custom made for one particular surveillance activity and arenot typically interchangeable with any other types of surveillanceactivity.

As such, multiple ground sensors must be manufactured in order toconduct various forms of surveillance activities. In this respect, thefinancial costs and manufacturing time associated with constructingdifferent versions of the narrowly-focused ground sensor may becomeburdensome and extensive.

Thus, there has long been a need in the industry, and in the aerospaceindustry in particular, for a ground sensor which is designed to beunalterable in direction during its aerial deployment towards a preciseground target. In addition, there is a need for a ground sensor which isadapted to perform various forms of surveillance activities as opposedto one specific one so as to eliminate the need for multiple versions ofthe same therefor.

The present invention addresses and overcomes the above-describeddeficiencies by providing a ground sensor assembly which utilizes aplurality of radially extending stabilizers for stabilization during itsaerial deployment to a precise ground location. Further to suchinnovative design feature, the ground sensor assembly of the presentinvention includes a plurality of sensor modules therewithin which canbe selectively chosen and interlocked to each other in a longitudinalstack formation depending upon the particular surveillance activity oractivities at hand. In this respect, not only can the ground sensorassembly of the present invention be accurately deployed, but it alsoeliminates the need to build and resort to multiple ground sensors forperforming various forms of surveillance activities.

BRIEF SUMMARY OF THE INVENTION

In accordance with the present invention, there is provided a groundsensor assembly adapted for deployment from air to a selected groundlocation. The ground sensor assembly comprises an aerially deployablesensor housing which has upper and lower housing ends. These two housingends define a longitudinally elongated aperture therebetween. Aplurality of connected sensor modules may be longitudinally insertedinto the aperture between the upper and lower housing ends.

Furthermore, an aerodynamic module may be connected to the sensormodules and be disposed adjacent the upper housing end outside theaperture. This aerodynamic module has a plurality of stabilizers whichradially extend outward therefrom and form a generally parallelrelationship with the upper housing end. Such stabilizers provideaerodynamic stability during the deployment of the ground sensorassembly from the air to the selected ground location.

More specifically, the sensor housing is preferably fabricated from ametallic material. In addition, a penetrating tip member may beconnected to the sensor modules and be disposed adjacent the lowerhousing end outside the aperture. The penetrating tip member may form apenetrating tip for penetrating the selected ground location after beingdeployed from the air. In the preferred embodiment, the penetrating tipmember has a conical configuration and is fabricated from a metallicmaterial such as steel.

In accordance with the present invention, the sensor housing maycomprise a plurality of aerial fins. The aerial fins may be formedadjacent the upper housing end and be radially extended outwardtherefrom. Preferably, there are four aerial fins formed to the upperhousing end. By such configuration, the aerial fins may provideaerodynamic guidance when the ground sensor assembly is deployed fromthe air to the selected ground location.

Moreover, a stop plate may be disposed between the aerodynamic moduleand the upper housing end. The stop plate may be outwardly extended in agenerally parallel relationship with respect to the stabilizers. Thestop plate is primarily utilized for controlling the ground sensorassembly into a controlled depth when penetrating the selected groundlocation. More specifically, the stop plate is designed to mitigate thepenetration of the sensor housing to expose the antenna above theselected ground location. The antenna may be located to extend above theaerodynamic module away from the upper housing end of the sensorhousing. In the preferred embodiment, the stop plate has a generallycircular configuration and defines a plate edge in which each of thestabilizers are extended therebeyond.

In accordance with the present invention, the sensor modules may beselected from the group consisting of a magnetic sensor, a seismicsensor, an acoustic sensor and combinations thereof. In the preferredembodiment, the sensor modules are axially interlocked to each other ina stack formation along the longitudinal axis of the sensor housing.Each of the sensor modules comprise a main module body, a collar and acapture ring. The main module body and the capture ring may be engagedto each other in a manner as to secure the collar therebetween. Thecollar may be freely rotatable between the main module body and thecapture ring.

In particular, the main module body has a main base end defining a mainthreaded portion externally therearound, whereas the collar has a collartop end defining a collar threaded portion internally therearound. Thecollar top end may be extended over the capture ring. This is so thatthe collar threaded portion can threadably engage the main threadedportion of an adjacent main module body.

Additionally, the main module body has at least one main hole. Thecapture ring has at least one capture hole. The main and capture hole(s)are preferably elongated along a same direction as the aperture of thesensor housing. The capture hole(s) may be aligned with the main hole(s)of an adjacent main module body and be sized and configured to besecured in position. This is to prevent the sensor modules from rotatingwith respect to each other.

In the preferred embodiment, each of the stabilizers are fabricated froma metallic material and have an elongated rod configuration. Furtherpreferably, there are three stabilizers radially extending outward fromthe aerodynamic module.

BRIEF DESCRIPTION OF THE DRAWINGS

These as well as other features of the present invention will becomemore apparent upon reference to the drawings wherein:

FIG. 1 is a perspective view of an aerially-deployable ground sensorassembly constructed in accordance with a preferred embodiment of thepresent invention and including a plurality of stabilizers whichradially extend outward therefrom;

FIG. 2 is a perspective exploded view of the ground sensor assemblyshown in FIG. 1 and illustrating its sensor housing which is adapted toaccommodate a plurality of stacked modules longitudinally therewithin;and

FIG. 3 is a perspective exploded view of one of the stacked modulesshown in FIG. 2 and illustrating its main module body and capture ringwhich secure a freely rotatable collar therebetween.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings wherein the showings are for purposes ofillustrating preferred embodiments of the present invention only, andnot for purposes of limiting the same, FIG. 1 perspectively illustratesa ground sensor assembly 10 constructed in accordance with a preferredembodiment of the present invention. The ground sensor assembly 10 isdesigned to maintain stable course of direction during its aerialdeployment and be selectively configurable to perform various forms ofsurveillance activities ranging from magnetic field, seismic and/oracoustic surveillance.

The ground sensor assembly 10 may be formed to have a variety of shapes,configurations, geometries and textures which produce suitableaerodynamics during its deployment from air to a targeted groundlocation (not shown). It should be noted herein that the ground sensorassembly 10 may be deployed from any aerial object such as an aircraftor be launched into the air by launching mechanisms such as a rocket ora cannon. Alternatively, a person of ordinary skill in the art willforesee that the ground sensor assembly 10 may be hand-placed at aspecific site of the target ground location in lieu of aerialdeployment.

Referring now to FIGS. 1 and 2, as the ground sensor assembly 10 may beany general desired shape it is understood that the ground sensorassembly 10 as depicted is symbolic in nature. However, the groundsensor assembly 10 of the present invention features a sensor housing 12which is elongated in a cylindrical-like configuration. Although thissensor housing 12 may be fabricated from any rigid material that canwithstand the impact of hitting the selected ground location, it ispreferably constructed from a metallic material. The sensor housing 12has an upper housing end 16 and a lower housing end 18 wherein anaperture 20 is longitudinally elongated along the sensor housing 12therebetween.

Referring more particularly to FIGS. 2 and 3, a plurality of sensormodules 22 are provided with the ground sensor assembly 10 of thepresent invention for the purpose of conducting various forms ofsurveillance activities about the targeted ground location. The sensormodules 22 are chosen from a group comprising of a magnetic sensor, aseismic sensor and/or an acoustic sensor. More specifically, one or moretypes of those sensors may be selectively utilized to conduct one ormore forms of surveillance activities corresponding to the selectedsensor. For example, if only one surveillance task is needed for aparticular mission, then only one specific type of sensor is utilizedwith the ground sensor assembly 10. However, if multiple surveillancetasks are desired for the mission, then different types of sensors maybe fitted together to take on the multiple tasks.

As illustrated in FIG. 2, the sensor modules 22 are placed within thesensor housing 12 in a very specific manner. More particularly, thesesensor modules 22 are connected to each other in a manner as to beinserted and fit within the longitudinal aperture 20 of the sensorhousing 12. Furthermore, it is preferred that the sensor modules 22become substantially contained between the upper and lower housing ends16, 18 when positioned within the aperture 20.

In order to satisfy such specification, it is preferred that the sensormodules 22 are axially interlocked to each other in a stackformation..along a longitudinal axis of the sensor housing 12 to conformto the elongated longitudinal spacing of the aperture 20. To derive thestack formation of the modules 22, certain portion of each module 22 areengaged to a complimentary portion of its adjacent module 22 to therebydefine the stack configuration.

Referring now back to FIG. 3, each of the sensor modules 22 are composedof a main module body 24, a collar 26 and a capture ring 28. In each ofthe modules 22, the main module body 24 and the capture ring 28 areengaged to each other and collectively secure the collar 26therebetween. The main module body 24 and the capture ring 28 maintainsthe securement of the collar 26 therebetween but provides some clearanceto allow the collar 26 to spin or rotate freely. In essence, each sensormodule 22 utilized in the ground sensor assembly 10 of the presentinvention follows this manner of construction.

Each main module body 24 has a main base end 30 which is disposed awayfrom its capture ring 28. This main base end 30 defines an externalsurface 32 that forms a main threaded portion 34 therearound. Inaddition, the collar 26 has a collar top end 36 which is sized andconfigured to extend over its capture ring 28 away from its main modulebody 24. The collar top end 36 defines an internal surface 38, in whicha collar threaded portion 40 is formed therearound.

With the particular features of the sensor modules 22 clarified, the wayin which sensor stack formation is formed could now be described. Moreparticularly, the collar top end 36 of a chosen sensor module 22 isplaced over the main base end 30 of an adjacent sensor module so thatthe internal surface 38 thereof is abutted against the external surface32 of the adjacent sensor module's main base end 30. They are designedto be complimentary so that the collar threaded portion 40 and the mainthreaded portion 34 can be threadably engaged to each other. Thisoperates to engage the two sensor modules 22 together in which suchprocess may be repeated to form the desired sensor stack configuration.

In addition to interlocking and stacking the sensor modules 22 together,the sensor modules 22 should be prevented from rotating with respect toeach other. To accomplish such end, a number of main holes 42 are formedthrough each of the main module body 24. A corresponding number ofcapture holes 44 are also formed through each of the capture ring 28. Inthe preferred embodiment, the main and capture holes 42, 44 areelongated along the same direction of extension as the aperture 20 ofthe sensor housing 12. The capture holes 42 of a particular sensormodule 22 may be placed in alignment with the main holes 44 of anadjacent sensor module 22 for fixed positioning. Although other measuresmay be used, it is preferred that guide pins (not shown) are insertedinto the capture holes 44 and through the main holes 42 of the nextadjacent sensor module 22. This should prevent the spinning of thesensor modules 22 relative to each other as the collar 26 is preferablytightened via a spanner wrench, for example. Optionally, gaskets (notshown) may be used between the main module body 24 and the capture ring28 to environmentally seal each individual module and to draw one module22 into contact with the other.

Because the sensor modules 22 are not allowed to spin with respect toeach other, standard electrical connections may be used. This simplifiesthe overall design of the ground sensor assembly 10 since slip ringconnections or extended wire lengths are not needed to account for therotation of the sensor modules 22. Such design is further advantageousover its predecessors because it also allows for ease of removal oraddition of modules 22. The assembly chain can be broken in any locationwithout requiring disassembly of the entire configuration for access toany individual module. In this respect, grouping of different types ofsensors 22 to monitor numerous phenomena such as seismic activities,acoustic disturbances and magnetic fields can be greatly facilitated.Furthermore, the commonality of both mechanical and electrical partsamong the different types of sensor modules 22 will also significantlyreduce the overall manufacturing costs and time.

Referring now to FIGS. 1 and 2, an aerodynamic module 46 is connected tothe sensor modules 22 in the same manner as described above. However,the positioning of the aerodynamic module 46 is specific in that it isdisposed adjacent the upper housing end 16 of the sensor housing 12outside its aperture 20. Preferably, only the sensor modules 22 arecontained within the aperture 20. This aerodynamic module 46 has aplurality of stabilizers 48 which are used for providing aerodynamicstability during the aerial deployment of the ground sensor assembly 10.

More specifically, the stabilizers 48 are adapted to stabilize theground sensor assembly 10 during its free fall towards the selectedground location. To accomplish such task, the stabilizers 48 aredesigned to radially extend outward from the aerodynamic module 46 whileforming a generally parallel relationship with respect to the upperhousing end 16 of the sensor housing 12. In the preferred embodiment,the ground sensor assembly 10 comprises three stabilizers 48, of whicheach stabilizer 48 has an elongated rod configuration and is fabricatedfrom a metallic material.

The ground sensor assembly 10 of the present invention further comprisesa plurality of aerial fins 50 for guiding the assembly 10 towards theselected ground location when being deployed from the air. These aerialfins 50 are preferably formed adjacent to the upper housing end 16 ofthe sensor housing 12 and radially extend outward therefrom. Preferably,four aerial fins 50 are used with the present ground sensor assembly 10.

There is also provided a penetrating tip member 52 for penetrating theselected ground location after its free fall thereto. In particular, thepenetrating tip member 52 is attached to the sensor modules 22 adjacentthe lower housing end 18 of the sensor housing 12 outside its aperture20. The penetrating tip member 52 defines a penetrating tip 54 oppositefrom its attachment to the sensor modules 22. The tip 54 is the portionwhich first penetrates the ground location. In the preferred embodiment,the penetrating tip member 52 has a conical configuration and isfabricated from a metallic material such as steel. Of course, if onewishes to hand-place the ground sensor assembly 10 as opposed todeploying it from the air, the penetrating tip member 52 may beoptionally eliminated from the overall design.

A stop plate 56 is provided between the aerodynamic module 54 and theupper housing end 16 of the sensor housing 12. The stop plate 56 isprimarily designed for controlling the penetration of the ground sensorassembly 10 into the selected ground location. This stop plate 56preferably has a generally circular configuration wherein it extendsoutwardly in a generally parallel relationship with respect to thestabilizers 48. It should be noted herein that the stabilizers 48 extendout beyond the edges 58 of the stop plate 56.

The stop plate 56 is adapted to mitigate or stop the penetration of theground sensor assembly 10 so as to expose at least a portion of theantenna 60 above the selected ground location. As shown in FIGS. I and2, the antenna 60 is extended above the aerodynamic module 54 away fromthe upper housing end 16 of the sensor housing 12. Similar to thepenetrating tip member 52, the stop plate 56 may be removed from theoverall design if the ground sensor assembly 10 is intended to behand-placed.

The ground sensor assembly 10 of the present invention may use a batteryor a battery pack (not shown) as its power source. However, if a longerlife battery configuration is desired, the battery or battery pack maybe removed and replaced by a cap assembly (not shown) adapted to befitted with a power cord. This may then be connected to an externalbattery of larger capacity which would be camouflaged above the groundlocation or buried nearby.

Additional modifications and improvements of the present invention mayalso be apparent to those of ordinary skill in the art. Thus, theparticular combination of parts described and illustrated herein isintended to represent only certain embodiments of the present invention,and is not intended to serve as limitations of alternative deviceswithin the spirit and scope of the invention.

1-21. (canceled)
 22. A method of deploying a ground sensor assembly fromair to a selected ground location, the method comprising the steps of:a) releasing the ground sensor assembly having an upper housing end anda plurality of stabilizers from the air; b) directing the ground sensorassembly towards the selected ground location; c) stabilizing the groundsensor assembly with the stabilizers radially extending in a generallyparallel relationship with respect to the upper housing end; d)penetrating the selected ground location to a controlled depth with theground sensor assembly; and e) performing a sensing activity of theselected ground location.
 23. The method of claim 22 wherein step b)comprises: 1) defining a plurality of aerial fins radially extendingoutward from the upper housing end; and 2) guiding the ground sensorassembly in the air toward the selected ground location with the aerialfins.
 24. The method of claim 22 wherein each of the stabilizers in stepc) have an elongated rod configuration.
 25. The method of claim 22wherein step d) comprises: 1) defining a penetrating tip member, a stopplate and an antenna of the ground sensor assembly; 2) penetrating theselected ground location with the penetrating tip member; and 3)mitigating the penetration of the ground sensor assembly with the stopplate to expose the antenna above the selected ground location.
 26. Themethod of claim 22 wherein step e) comprises: 1) defining a plurality ofsensor modules inserted within the ground sensor assembly in a stackformation; and 2) sensing the selected ground location with the sensormodules.
 27. The method of claim 26 wherein the sensor modules areselected from the group consisting of a magnetic sensor, a seismicsensor, an acoustic sensor and combinations thereof.